A spokesperson for the organisers of the event said that the walk had been given approval by Lyra's family and partner Sara Canning.

They said that the walk "will not become a platform for politicians or political groups".

"In 1998, the people of Ireland, north and south, signed the Belfast Agreement. It was an agreement to respect each others' differences and work together to create a better future, for ourselves and future generations," the spokesperson said.

"This was not just an agreement to task our politicians with ironing out our political differences - it was a contract, which we all signed, and which we should carry with us everywhere we go. It is a contract which should guide us in how we treat others and how we expect to be treated. The Good Friday Agreement is not perfect, but it sets out in black and white the terms of a contract designed to bring about peace.

"21 years after we signed this contract, another young, talented life was snuffed out in an instant, by people who didn't sign up to this contract. We cannot stand by idly while a tiny minority cause heartbreak like this any more."

Lyra McKee's funeral is set to take place at St Anne's Cathedral in Belfast at 1pm on Wednesday.

Secretary of State Karen Bradley and Irish President Michael D. Higgins are set to be in attendance alongside the leaders of Northern Ireland's main political parties.